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Brake pedal went down, have to pull back up?

Under Pressure

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Applied the PB’s on my 70 GTX, car stopped fine, pedal won’t come back up unless I use my foot under it to pull back up, drove the car home and braking was normal, just had to keep pulling the pedal up to free up the brakes
- stock 4 wheel drum car
- pulled check valve from booster and is operating.
- fluid was very low in front (for the rears) and MC lid was leaking fluid (found gasket cracked and leaking pretty good)
- might have sucked some air
- No leaks at wheels
Booster? MC? Never had a pedal stay down from air in lines.
Have not bleed wheel cylinders yet.
All suggestions appreciated before I start pulling apart
Thanks, Bill
 
My first guess would be the MC.
Usually if the booster goes, you have to stand on the pedal to get it to stop.

The lost fluid might be entering the booster.
 
My first guess would be the MC.
Usually if the booster goes, you have to stand on the pedal to get it to stop.

The lost fluid might be entering the booster.
Thanks, looks like I’ll start with the MC, and then check for fluid in the booster
 
Probably not related but....
My brother in law's 72 Duster sat in a field for years and had surface rust on every unpainted surface including the under dash metal components....including the clutch and brake pedals, push rods and shift linkage. I had to swap to different pedals to get them to swing without binding.
 
Probably not related but....
My brother in law's 72 Duster sat in a field for years and had surface rust on every unpainted surface including the under dash metal components....including the clutch and brake pedals, push rods and shift linkage. I had to swap to different pedals to get them to swing without binding.
Hadn’t given that a thought, but definitely worth getting under there tonight to see if anything is binding up, gonna pull all the drums too and make sure all springs are in place and retracting
Thanks Greg
Bill
 
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Well after checking all the pedal linkage and finding in good order, I pull the MC, and looking in the booster I found this mess of pieces, and the push rod flopping about.
New booster on order with my favorite parts store New-5 Auto, he located one and will have Wednesday.
I have never had a more exhausting and cuss filled morning working on getting those 4 bolts out under the dash, drivers seat is coming out for the re-install, lol
 
The seats removed makes it much easier. If you use a universal joint when installing wrap u-joint with electrical tape so it only flops only a little. You bend it by hand if you need more flex. I use a deep socket, the nuts in my car had captive star washers so they don't go deep in socket.
 
I've posted many times about an ongoing hassle with my brakes, front disk conversion. The pedal sinks down quite a bit; but doesn't engage the brakes. If I press further then brakes work fine. The pedal stays down and have to pull it back up with some resistance despite the booster return spring that should snap it back. My guess is a faulty valve or leak down within the booster. Anyway, things seem to point to a bad booster and have been waiting friggin weeks and weeks from Jeg's to deliver. Yeah I now take out the driver's seat when having to work under the dash; at my age I can't handle the squeeze and twist play anymore. Still a bitch even with the seat out.
 
Pedal staying down is usually the booster. A good check is when this happens, pull the little check valve and hose off the booster. Air will suck in but if the pedal pops back up you’ve got a booster problem.
 
I've posted many times about an ongoing hassle with my brakes, front disk conversion. The pedal sinks down quite a bit; but doesn't engage the brakes. If I press further then brakes work fine. The pedal stays down and have to pull it back up with some resistance despite the booster return spring that should snap it back. My guess is a faulty valve or leak down within the booster. Anyway, things seem to point to a bad booster and have been waiting friggin weeks and weeks from Jeg's to deliver. Yeah I now take out the driver's seat when having to work under the dash; at my age I can't handle the squeeze and twist play anymore. Still a bitch even with the seat out.
I took it in to a reliable non chain auto parts store I’ve dealt with for years, he made a couple calls and found one from another parts store he works with, I hear you about Jegs, last summer I ordered 2 new magna flow mufflers, one showed up in a week, and they were no help helping me locate the other one, they admitted to tracking number errors, I got the other one 2 weeks later
I am not much of an online buyer, I’ll drive to the right place if I have to, plus I like talking to people that have experience and know what the hell they’re talking about, like the people on this site, and good ole independent auto parts stores
 
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